The present invention relates to a measurement system and more particularly to a measurement system that activates a measurement device based on a recipe.
Semiconductor wafer inspection devices, such as CD-SEMs (Critical Dimension-Scanning Electron Microscopes), inspect semiconductor wafers according to a recipe. The recipe describes an inspection procedure and inspection conditions and its recipe parameters vary according to a kind of wafer, a lot and a process.
The recipe, if not set with correct recipe parameters conforming to a wafer to be inspected, won't work normally and therefore needs to be managed so that inspections can be performed with right recipes at all times.
For this purpose, it is general practice to allow only those users with a predetermined authority to prepare and edit recipes, the users being operators engaged in the operation of a semiconductor wafer inspection device in a semiconductor manufacturing line.
Normally, an authority for operation including generation and editing of recipes is given as follows.
An operator of the device is identified and authenticated before he or she starts operating the device and, from that moment on, all operations performed on the device are recognized as having been performed by that operator. Therefore, the authority to use the device and parameter settings are those of the operator authenticated at that time.
When another operator uses the device, he is required to take the same identity and authentication procedure. In practice, however, this procedure is not carried out because it is troublesome (complicated). Thus a problem arises that this operator happens to be able to operate the device under the identification and authority of the previously authenticated operator.
To deal with this problem, a method has been disclosed in JP-A-2006-60157 which allows only a particular operation for operators without requiring them to enter their identifier.
However, the above patent has a problem that, when the device is in the process of wafer inspection, it is not possible to switch the authority and setting to those of another operator for device operation.
Consider a case, for example, in which after an authenticated operator A has started a wafer inspection based on a recipe, another operator B, while the first operator A is away, prepares a recipe to be used next. In this case the following problem arises.
The operator B checks the content of the recipe and must edit problems as they arise. Since the device is in the process of wafer inspection, outputting various data associated with the authority and settings of the operator A and displaying the operation state, it is not possible to switch from operator A to operator B while keeping the wafer inspection under way.
In the current situation, once a user authentication is carried out, anybody can edit device data such as recipes, making it impossible to manage the recipes properly. If on the other hand the user authentication is carried out strictly, the user cannot be changed while the recipe is being executed (during the wafer inspection) and therefore one must wait for the completion of the current wafer inspection before the user can be switched.